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clinuxrulz/automerge-proxy.ts

Created June 7, 2025 22:48
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automerge-proxy.ts
export function projectMutableOverAutomergeDocV2<T extends object>(
json: any,
updateJson: (cb: (json: any) => any) => void,
typeSchema: TypeSchema<T>
): T {
if (typeof typeSchema != "object" || typeSchema.type != "Object") {
throw new Error("Expected object.");
}
let properties = typeSchema.properties;
let result = new Proxy<T>(
{} as T,
{
defineProperty(target, property, attributes) {
console.log("defineProperty", target, property, attributes);
return Reflect.defineProperty(target, property, attributes);
},
deleteProperty(target, p) {
console.log("deleteProperty", target, p);
return Reflect.deleteProperty(target, p);
},
getOwnPropertyDescriptor(target, p) {
console.log("getOwnPropertyDescriptor", target, p);
if ((properties as any)[p] != undefined) {
let r = Reflect.getOwnPropertyDescriptor(properties, p);
if (r == undefined) {
return;
}
r = { ...r, };
r.value = (result as any)[p];
return r;
}
return Reflect.getOwnPropertyDescriptor(target, p);
},
getPrototypeOf(target) {
console.log("getPrototypeOf", target);
return Reflect.getPrototypeOf(target);
},
has(target, p) {
console.log("has", target);
if ((properties as any)[p] != undefined) {
return true;
}
return Reflect.has(target, p);
},
isExtensible(target) {
console.log("isExtendable", target);
return Reflect.isExtensible(target);
},
ownKeys(target) {
console.log("ownKeys", target);
return [
...Reflect.ownKeys(properties),
...Reflect.ownKeys(target),
];
},
preventExtensions(target) {
console.log("preventExtensions", target);
return Reflect.preventExtensions(target);
},
setPrototypeOf(target, v) {
console.log("setPrototypeOf", target, v);
return Reflect.setPrototypeOf(target, v);
},
get(target, p, receiver) {
if (typeof p == "symbol") {
return (target as any)[p];
}
if (typeof p == "string") {
let propertySchema = (properties as any)[p] as TypeSchema<any>;
if (propertySchema != undefined) {
if ((propertySchema as any).type == "Object") {
return projectMutableOverAutomergeDocV2(
json[p],
(cb) => updateJson((json2) => cb(json2[p])),
propertySchema,
);
} else if ((propertySchema as any).type == "Array") {
return projectMutableOverAutomergeDocArrayV2(
json[p],
(cb) => updateJson((json2) => cb(json2[p])),
propertySchema,
);
}
let r = loadFromJsonViaTypeSchema(
propertySchema as any,
json[p]
);
if (r.type == "Err") {
return makeDefaultViaTypeSchema(propertySchema as any);
}
return r.value;
}
}
return Reflect.get(target, p, receiver);
},
set(target, p, newValue, receiver) {
if (typeof p == "symbol") {
(target as any)[p] = newValue;
return true;
}
if (typeof p == "string") {
let propertySchema = (properties as any)[p] as TypeSchema<any>;
if (propertySchema != undefined) {
let r = saveToJsonViaTypeSchema(propertySchema, newValue);
updateJson((json2) => json2[p] = r);
return true;
}
}
return Reflect.set(target, p, newValue, receiver);
},
},
);
return result;
}
export function projectMutableOverAutomergeDocArrayV2<T extends object>(
json: any,
updateJson: (cb: (json: any) => any) => void,
typeSchema: TypeSchema<T>
): T {
if (typeof typeSchema != "object" || typeSchema.type != "Array") {
throw new Error("Expected object.");
}
let elementSchema = typeSchema.element;
let iterator = function*() {
for (let i = 0; i < json.length; ++i) {
yield (result as any)[i];
}
};
let result = new Proxy<T>(
[undefined] as T,
{
defineProperty(target, property, attributes) {
console.log("defineProperty", target, property, attributes);
return Reflect.defineProperty(target, property, attributes);
},
deleteProperty(target, p) {
console.log("deleteProperty", target, p);
return Reflect.deleteProperty(target, p);
},
getOwnPropertyDescriptor(target, p) {
console.log("getOwnPropertyDescriptor", target, p);
let idx = (typeof p == "string") ? Number.parseInt(p) : undefined;
if (Number.isNaN(idx)) {
idx = undefined;
}
if (idx != undefined) {
let r = Reflect.getOwnPropertyDescriptor(target, 0);
if (r == undefined) {
return;
}
r = { ...r, };
r.value = (result as any)[p];
return r;
}
return Reflect.getOwnPropertyDescriptor(target, p);
},
getPrototypeOf(target) {
console.log("getPrototypeOf", target);
return Reflect.getPrototypeOf(target);
},
has(target, p) {
console.log("has", target);
let idx = (typeof p == "string") ? Number.parseInt(p) : undefined;
if (Number.isNaN(idx)) {
idx = undefined;
}
if (idx != undefined) {
return 0 <= idx && idx < json.length;
}
return Reflect.has(target, p);
},
isExtensible(target) {
console.log("isExtendable", target);
return Reflect.isExtensible(target);
},
ownKeys(target) {
console.log("ownKeys", target);
return [
...Array(json.length).fill(undefined).map((_,idx) => idx.toString()),
...Reflect.ownKeys(target).filter((key) => key != "0"),
];
},
preventExtensions(target) {
console.log("preventExtensions", target);
return Reflect.preventExtensions(target);
},
setPrototypeOf(target, v) {
console.log("setPrototypeOf", target, v);
return Reflect.setPrototypeOf(target, v);
},
get(target, p, receiver) {
if (p == Symbol.iterator) {
return iterator;
}
if (typeof p == "symbol") {
return (target as any)[p];
}
if (typeof p == "string") {
let idx = (typeof p == "string") ? Number.parseInt(p) : undefined;
if (Number.isNaN(idx)) {
idx = undefined;
}
if (idx != undefined && 0 <= idx && idx < json.length) {
if ((elementSchema as any).type == "Object") {
return projectMutableOverAutomergeDocV2(
json[idx],
(cb) => updateJson((json2) => cb(json2[p])),
elementSchema as any,
);
} else if ((elementSchema as any).type == "Array") {
return projectMutableOverAutomergeDocArrayV2(
json[idx],
(cb) => updateJson((json2) => cb(json2[p])),
elementSchema as any,
);
}
let r = loadFromJsonViaTypeSchema(
elementSchema as any,
json[idx]
);
if (r.type == "Err") {
return makeDefaultViaTypeSchema(elementSchema as any);
}
return r.value;
}
}
return Reflect.get(target, p, receiver);
},
set(target, p, newValue, receiver) {
if (typeof p == "symbol") {
(target as any)[p] = newValue;
return true;
}
if (typeof p == "string") {
let idx = (typeof p == "string") ? Number.parseInt(p) : undefined;
if (Number.isNaN(idx)) {
idx = undefined;
}
if (idx != undefined) {
let r = saveToJsonViaTypeSchema(elementSchema as any, newValue);
updateJson((json2) => json2[p] = r);
return true;
}
}
return Reflect.set(target, p, newValue, receiver);
},
},
);
return result;
}
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